Shooting in The Wind

[Dphar]

This is not an absolute but just the basics.
How fast a bullet is going is not the ultimate determining factor in wind drift. Its the time the bullet loses in transit due to velocity loss. Thus if the MV with no drag would give a time of flight of .010 second but with drag its .017 sec the difference is the cause of the wind drift in a specific x-wind. Or so I have read. Thus wind drift is not how far the air moves in a specific time frame.
Modern HV bullets with high sectional density loose FAR less time and drift less. Modern super low drag match bullets have BCs approaching or even exceeding 1.0.
A 15 mph x-wind will produce enough drift to cause misses/bad hits on deer sized animals at 100 yards. Note that Lyman gives a .535 RB a BC of .075. In a 10MPH wind this just over 9" of drift a 100 when started at 1900 fps. At the same velocity a .445 with a .063 BC drifts just over 11"
This from Lymans Blackpowder Handbook.
Smaller balls are less.
20 mph head or tail wind at 100 only changes impactpoint about .15"+-
[url] http://www.handloads.com/calc/[/url]
will provide trajectory and other ballistic information but their BC calculator produces far too high a BC for RBs. When used with Lyman's BCs it produces results similar to Lyman's data.

Lymans figures are.
.350 .049 bc
.440 .062 bc
.495 .070 bc
.562 .079 bc
.735 .104 bc

Dan

 

[Dave Rosenthal]

Don't be a worry-wimp! A little wind is just something to enjoy at the range! I've actually participated in BP rifle competitions where the weather went from dead calm to 40 MPH gusts as a cold front moved through, dropping huge snowflakes and turning the range from bright sun to deep overcast conditions TWICE during the same match! You just have to "suck-it-up" and do the best that you can. Eventually everyone encounters some sort of weather annomily during a match, so it all evens-out in the long run!

NOW, that all being said, here goes some PRB blasphemy: When mother nature starts the wind a blowin' I use .50 cal 370 grain T/C Maxi-Balls and pop-up my charge to about 90 grains of 3Fg Goex and hurl those huge chunks of lead at better than 1500 FPS! Greater mass means less wind effect AND cause it's not a PRB, it doesn't lose too much in the speed dept. either. Less "hang-time" in the air also results in less wind resistance. You just take your sighters and adjust for the prevailing wind, shooting when you feel as little gusts as possible.

Yes, your shoulder does tell you that you shot something, but I WIN competitions this way when others wimp-out! I'm not bragging mind you, just giving a factual opinion.

May you always have fun making smoke!

Dave

 

[burgessrudy]

Thanks Guys. As it turned out, the weather was better than forecasted( These meteorologists and Al Gore are the guys who are sure of Global Warming but they can't get the weather right two days out). Anyway, it was a little windy and I shot mostly off-hand for the first time and hit a bulls-eye and three separate groups of two within the 8 and 9 rings left and right at 62 yards. That's the best shooting I have done with this gun so far and was very pleased.

 

[Halftail]

Gee,
If I only hunted or went to the range around here when the wind didn't Blow.I'd never[url] shoot.In[/url] the same breath...if it was Blowing 150 MPH with Gusts up to 200 I just wouldn't bother to Crawl up into my Treestand. :rotf:

 

Under those conditions there wouldn't be anything moving anyway. May as well stay warm and cozy as the deer are on a day like that.